Life - Open Source

...as sweet as chocolate, as turbulent as the ocean

I like answering polls, and I think many others do also. I hardly ever use this feature of my permanent account. So I've been thinking I should do it more often, and today I've been thinking about open-source.

LiveJournal is open-source (for the most part), and we are all using it. Do you know what open-source means? Do you use other open-source stuff? How do you like it?